Learning speedsurfing online is not only practical lessons about how to rig or stand on the board. GPS-Speedsurfing.com is a good source for information. Try to find out what brands suits your style best, after this I would suggest to check out GPS-speedsurfing.com for the right sizes (should you take the 100 or the 112 liter board, which one is faster??) Lots of sponsored riders show what combination work out great, making it easier for you to choose the right equipment! Goldmembership is highly recommended, this actually can safe a lot of experimenting/money.
To start I would advice these Guides:
When you would like to buy (new or used) gear for speedsurfing I advice this article: